The invention relates to a method for the production of a textile strip, by preparing and aftertreating an intermediate product, with the textile strip having long weft elements, especially long weft threads, provided diagonally to the strip length, intersecting one another, and connected by longitudinal rows of stitches.
Furthermore, the invention relates to a textile strip, produced according to the method of the invention, as well as to a device on a warp knitting machine, particularly a stitch knitting machine, having at least one movable weft laying device for working long weft elements or weft threads, which extend over the entire working width, into the textile strip.
The invention further relates to a warp-knitting machine, especially a sewing-knitting machine, a production method and a warp-knit fabric. The warp knit fabric may also be referred to as a sloping product. To connect weft elements with stitch forming warp threads, a warp knitting machine uses a conventional needle system.
A method is known for the production of thread knitted textile strips with diagonally running long weft threads on a warp knitting machine, as well as thread knitting machines which when being used, make it necessary to design the operative width of the weft laying device, so that the distance from the first to the last thread of the weft thread group to be placed corresponds to a one to three and a half time expansion of the working width of the machine (Japanese patent application No. 42-67693).
If zig-zag like long weft threads are to intersect at an angle of 90.degree., or if the angle between the weft threads and a fictitious straight line, extending at right angles to the edge of the fabric, is to be 45.degree., the operative width of the weft laying device (which corresponds to the width of the long weft thread group to be placed) is twice as long as the working width of the machine. If the angle, formed by the long weft threads with the fictitious straight line is 60.degree., then the operative width of the weft laying device has to be approximately mately three and a half times the working width. At a working width of 3.5 m, which is the customary width for thread knitting machines, the weft laying device would have to be more than 10 m wide, and correspondingly massive.
Such a weft laying device merely allows a relatively slow mode of operation, which in most cases is not economically justifiable.
The described method is accomplished by a weft laying device, which moves back and forth at right angles in relation to the length of the textile strip. The placed group of long weft threads is guided by two weft thread transport means, into which the long weft threads are hung in the direction of a stitch formation zone, at which point the weft threads join the warp threads, forming a textile strip.
Methods and equipment for the production of warp-knit fabrics or sewn-knitted single sloping products and double sloping products are also known.
For example, as disclosed in U.S. Pat. No. 4,567,738, FIGS. 1 to 4, a single sloping product, comprising a group of filling threads, is produced owing to the fact that a single product with filling threads, which originally are at right angles to the longitudinal axis of the product, are distorted obliquely in an additional production step, to bring about an oblique adjustment of the filling threads relative to the longitudinal axis.
A double sloping product of two groups of filling threads can be produced according to this method by obliquely distorting two single products having filling threads, which are originally at right angles to the product, in separate production steps and subsequently combining them with one another in the nature of warp-knitting or sewn-knitting in yet another production step. At the same time, the single sloping products formed are placed next to one another in such a manner, that the oblique filling threads cross each other. If an additional linear assemblage of fibers is supplied to the two single sloping products before the latter are combined, the double sloping product will have a third structure axis, which is woven on during the process of combining the single sloping products. Because of the separate production of the single sloping products with filling threads originally at right angles and the subsequent treatment of these products, the method is relatively expensive.
A further known method and the equipment associated therewith (U.S. Pat. No. 4,567,738, FIGS. 5, 6 and 11, and Japanese Patent Application No. 42-67 693) start out from the idea of producing a warp-knitted or sewn-knitted single sloping product directly, without previously making a single product with filling threads originally at right angles in a separate production process. The method is carried out with a filling laying device, which moves back and forth at right angles to the length of the single sloping product. The laid group of filling threads is guided by two filling-thread transporting means, in which the filling threads are suspended, into a stitch-forming location, where the filling threads are combined with stitch-forming warp threads.
If a rather large angle of slope of the filling threads is desired and the single sloping product is to have an essentially linear edge, it is necessary to design the effective width of the filling laying device in such a manner, that the distance between the first and the last thread of the filling-distance thread group to be laid is a very long distance, which may be appreciably longer than the working width of the machine. Accordingly, if the filling threads, disposed in zigzag fashion, are to cross each other at an angle of 90.degree., or if the angle between the filling threads and an imaginary straight line, which extends at right angles to the edge of the fabric, is to amount to 45.degree., the effective width of the filling laying device (corresponding to the width of the group of filling threads that is to be laid) is twice as long as the working width of the machine. If the angle, which is formed by the filling threads with the imaginary straight line, is 60.degree. effective width of the filling laying device must even be approximately three times the working width.
For a working width of 3.5 m, which is customary for relevant machines, the filling laying device alone would be more than 10 m wide and also correspondingly heavy. A filling laying device with an extended effective width and a corresponding structural size permits only a relatively slow mode of working, which is not economic in most cases.